According to an aspect, a display device includes: a position information acquiring unit that acquires position information on a position of a viewer; a separation unit that changes a position of an image separator based on the position information; an illumination unit that changes a direction of an optical axis of illumination light based on the position information of the viewer in synchronization with a timing at which the position of the image separator is changed; and a display unit that modulates the illumination light and displays an image including plural parallax images.